Background: Fibromyalgia is a chronic pain syndrome associated with sleep disorders, fatigue and psychological symptoms. Combinations therapies, such as electrotherapy and therapeutic exercises have been used in the clinical practice.

Aim: To assess the efficacy of high-frequency transcutaneous electrical nerve stimulation (TENS) as an adjuvant therapy to aerobic and stretching exercises, for the treatment of fibromyalgia.

Design: Controlled clinical trial.

Setting: Unit of rehabilitation of a public hospital

Population: Twenty-eight women aged 52.4±7.5 years, with fibromyalgia.
Methods: A visual analogue scale measured pain intensity; tender points pain threshold, by dolorimetry; and quality of life, by the Fibromyalgia Impact Questionnaire. All subjects participated in an eight-week program consisting of aerobic exercises, followed by static stretching of muscle chains. In TENS group, high-frequency (150 Hz) was applied on bilateral tender points of trapezium and supraspinatus.

Results: TENS group had a greater pain reduction (mean change score=-2.0±2.9 cm) compared to Without TENS group (-0.7±3.7 cm). There was a difference between mean change scores of each group for pain threshold (right trapezium: 0.2±1 kg/cm² in TENS group and -0.2±1.2 kg/cm² in Without TENS group). In the evaluation of clinically important changes, patients receiving TENS had relevant improvement of pain, work performance, fatigue, stiffness, anxiety and depression compared to those not receiving TENS.

Conclusion: It has suggested that high-frequency TENS as an adjuvant therapy is effective in relieving pain, anxiety, fatigue, stiffness, and in improving ability to work of patients with fibromyalgia. Clinical rehabilitation impact: High-frequency TENS may be used as a short-term complementary treatment of fibromyalgia.